<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <div id="app">
        <h2 v-bind:index="attr">{{title}}</h2>
        <h2 :index="attr">{{title}}</h2>
        <h2 :index="'attr'">{{title}}</h2>
        <h2 index="attr">{{title}}</h2>
    </div>

    <script src="https://cdn.jsdelivr.net/npm/vue@2/dist/vue.js"></script>
    <script>
        let vm = new Vue({
            el : '#app',
            data :{
               title : '东软睿道',
               attr : 'hello'
            },
        });
    </script> 
</body>
</html>